Antimicrobial activity of silver salt and silver nanoparticles in different forms against microorganisms of different taxonomic groups

[Display omitted] •The resistance of pathogenic microorganisms to silver nanoparticles and ions in liquid and solid media has been investigated.•Silver nanoparticles in various forms were obtained by chemical reduction and biological methods.•The resistance to silver nanoparticles and ions was investigated in different growth phases of pathogenic microorganisms. The development of antiseptics and medical products (bandaging materials, sponges, etc.) based on silver nanoparticles is an essential task due to the growing resistance of pathogenic microorganisms to medicines long used in clinical practice. Using silver nanoparticles for the same purpose is promising, but the potential hazards and cumulative effects in the application of nanoparticles requires a thorough study of those materials. To evaluate the efficiency of antiseptics and medical products based on silver nanoparticles, it is necessary to conduct an in-depth study of the activity of silver nanoparticles in different forms and immobilized in carriers. The study examines the resistance of bacterial and fungal cultures to silver nanoparticles produced by chemical reduction and microbiological synthesis. The study of resistance was carried out in different growth phases of pathogenic microorganisms and in both liquid and solid media. Chemically and microbiologically synthesized nanoparticles were added in the form of a suspension, as well as encapsulated in chitosan-PVA matrices. It was experimentally discovered that, depending on the medium and form of the silver, the antibacterial effect would significantly differ due to changes in the mechanisms regarding the release of nanoparticles and their activity against the cells of pathogenic and potentially pathogenic microorganisms.